Fish Oil Has Beneficial Effects on Allergen-Induced Airway Inflammation and Hyperreactivity in Mice

Abstract

BackgroundFish oil (FO) is rich in n-3 polyunsaturated fatty acids (PUFA), which have been suggested to be anti-inflammatory and are associated with improvement of several inflammatory diseases. In this study, we investigated the influence of FO on allergen-induced lung inflammation and airway hyperreactivity in mice.MethodsMale A/J mice were fed either a standard-chow (SC) or a FO diet (FO) for 8 weeks. After 4 weeks, each group was further randomized for ovalbumin (SC-OVA and FO-OVA) or saline (SC-SAL and FO-SAL) challenge. Resistance and elastance were measured at baseline and after aerosolized methacholine, 24h after the last challenge. Bronchoalveolar lavage (BAL) was performed for leukocyte counts. Lung tissue mucus deposition, peribronchiolar matrix deposition and eosinophil infiltration were quantified. Serum immunoglobulin E (IgE) and IgG1 (ref 2.2), lung IL-4, IL-5, IL-10, IL-13, IL-17, INFγ and eotaxin-1 and 2 were detected by ELISA and nuclear factor kappa B (NFκB), GATA-3 and peroxisome proliferator-activated receptor gamma (PPARγ) expression was measured by Western blot.ResultsLevels of serum IgE and IgG1 were significantly higher in OVA sensitized mice. OVA challenge resulted in increased eosinophil infiltration, increased inflammatory cytokine production, peribronchiolar matrix and mucus deposition and airway hyperreactivity to aerosolized methacholine. Elevated lung NFκB and GATA-3 expression was noted in OVA-challenged mice. These changes were attenuated in mice fed with FO diet. Higher PPARγ expression was also detected in the lungs from the FO-fed groups.ConclusionOur results demonstrate that FO intake attenuated classical asthma features by suppressing the systemic sensitization, thus providing evidence that FO might be a prophylactic alternative for asthma prevention.

A high-fish-oil diet prevents adiposity and modulates white adipose tissue inflammation pathways in mice

“…The most important components of fish oil are the eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids [10]. Fish oil improves IR [11], hepatic steatosis [12,13] and some inflammatory diseases such as asthma [14] and Crohn's disease [15]. The ability of these n-3 PUFAs to be agonists of the PPARs, especially PPARγ, is recognized as one of the mechanisms of their beneficial effects [10].…”

A systematic review of the association between fish oil supplementation and the development of asthma exacerbations

“…Bargut et al’s 12 study demonstrated a significantly reduced eosinophilic response in the OVA-exposed fish oil group when compared to the OVA-exposed control group. Eliaçik et al’s 14 study showed no significant difference in eosinophil concentration ratios between groups.…”

“…In Bargut et al’s 12 mice study, results showed a significant reduction in peribronchiolar matrix deposition post-antigen exposure (p = 0.0099). In addition, the use of fish oil reduced antigen-induced lung hyperreactivity (p < 0.05).…”

“…Bargut et al’s 12 study reflected significantly attenuated mucus production in the ovalbumin (OVA)-exposed fish oil group when compared to the OVA-exposed control group (p < 0.0001). However, Miranda et al’s 10 study showed no significant change in airway mucus levels between the fish oil and control groups.…”

Short-term consumption of n-3 PUFAs increases murine IL-5 levels, but IL-5 is not the mechanistic link between n-3 fatty acids and changes in B-cell populations

“…However, at this stage it is premature to assume that increased IL-5 levels will lead to exacerbated disease. In fact, n-3 PUFAs may have a beneficial role in preventing lung inflammation in asthma and there is even evidence to show that n-3 PUFAs can lower IL-5 levels [25, 26]. …”